How Can I Safely Pass a PHP Variable to JavaScript?

Sharing a PHP Variable with JavaScript

When working with PHP and JavaScript, it's often necessary to exchange data between the two environments. One common scenario involves passing a PHP variable to a JavaScript variable, especially when the variable contains special characters like quotes and newlines.

Solution: Encoding with JSON

To encode a PHP string suitable for output as a JavaScript variable, utilize the json_encode() function. This method efficiently converts the PHP string into a JSON-formatted string, which can then be safely incorporated into a JavaScript variable.

Code Example:

<script>
  var myvar = <?php echo json_encode($myVarValue, JSON_UNESCAPED_UNICODE); ?>;
</script>

Additional Considerations:

• Ensure your PHP version is 5.2.0 or later.
• The PHP variable ($myVarValue) should be UTF-8 encoded for optimal compatibility.
• If the encoded value is used in an HTML attribute (e.g., onclick), use htmlspecialchars() to prevent potential issues with special characters being misinterpreted as HTML entities.

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